Digital image processing typically employs two dimensional image convolutions. The standard form for a discrete two-dimensional image convolution is ##EQU2## where f(m,n) is the convolution mask, and g(x,y) is the image array to be processed. An implementation of this function would require ##EQU3## multiply operations to convolve g(x,y) with f(m,n). If the quantity (x)(y) is much greater than the quantity (m)(n), this can be approximated by (m)(n)(x)(y).
It would therefore represent an advance in the art to provide a two-dimensional image convolution which requires a reduced number of multiple operations.